Most Frequent Lennox® Furnace Error Codes (and What They Mean)

December 06, 2019

While your Lennox® furnace cannot talk to you, it has a process to get your attention when there’s a furnace error.

Its control board has double LED lights that can share a fault code. Based on the fault, your heating system could show solid or flashing lights.

While there are some simple heating fixes you can complete yourself, many fixes are best taken care of by HVAC technicians. When your heater will not kick on or deliver warmth, reach out to Dearing's Service & Solutions at 812-200-5844 for expert furnace repair in Huntingburg.

Our technicians will rapidly detect and repair the failure, even if you don’t use a Lennox heating system. We can repair all types or configuration—and get the warmth reintroduced to your house fast.


What Does the Blinking Light on My Heating System Mean?

Your heater relies on lights to flash code when it is malfunctioning. It also uses these lights to relay it’s heating like it should.

Regular heating includes:

  • Simultaneous slow flash—heater operating correctly.
  • Simultaneous fast flash—heater is beginning to call for heat.

If you realize that one light going on and off slowly and the other going on and off rapidly, your heating system might have a low flame signal. This can occur even when your furnace is running properly. It signifies the flame sensing rod could have build-up or in the wrong area on the burner. Contact us at 812-200-5844 for support.

Here are several other of the most routine problems for Lennox HVAC systems.

Furnace Refuses to Start

Here are some of the light sequences you could observe when your heater won’t turn on or stay on. The bulk of these problems need to be taken care of by a professional, for instance from Dearing's Service & Solutions.

  1. The duo of LED lights aren’t lit. This means your heater might not have electricity. Look at the breaker box to ensure the heater fuse hasn’t flipped. Try resetting the fuse if it has moved into the “off” position. If it promptly turns off following a reset, leave the breaker alone and contact us at 812-200-5844.
  2. One light is solid and the other is flashing slowly. This signifies the flame rollout switch is likely open. The part is a critical safety guard that helps in avoiding fires and carbon monoxide. You shouldn’t try to fix this problem on your own.
  3. One light is flickering rapidly and the other is blinking slowly. This typically means power polarity has been transposed. Your heater may have a wiring problem that requires professional support from Dearing's Service & Solutions.
  4. The pair of lights are blinking slowly. This means your heater’s blower motor likely isn’t running. This part distributes heated air from the HVAC system into your residence. We can assist in determining what’s causing an issue with this piece.
  5. One light is blinking slowly and the other is flickering fast. This signifies your furnace might have low voltage or a short circuit. Get in touch with our experts at 812-200-5844 for help.
  6. One light is blinking on, on and off while the other blinks on, off, on. This means there might be a fault with your HVAC system’s motherboard or wiring. Dearing's Service & Solutions can locate the issue and take care of it.
  7. Both lights display alternate slow blinks. This signifies your HVAC system may have a flame issue. There may be an issue with its gas supply, gas valve or ignitor control. Contact us at 812-200-5844 for assistance.
  8. One light flashes slowly while the other remains steady. This usually means your heating system’s limit switch is malfunctioning. The switch keeps your HVAC equipment from overheating. Reach out to the experts at Dearing's Service & Solutions for assistance.

Heater Blower Operates But No Warmth

Here’s what may be at fault when you notice your heating equipment’s blower fan on, but you aren’t receiving any warmth.

  • Both lights are giving alternating rapid flickers. This signifies your furnace ignitor might not be working. This part ignites fuel in your heating system to make heat and should be fixed by a technician from Dearing's Service & Solutions.

Trust Us for Expert Furnace Repair

When you need to have your HVAC equipment fixed fast, trust the specialists at Dearing's Service & Solutions. Our pros will take care of the fault right away and have your space feeling cozy again in a short time. Contact us at 812-200-5844 or contact us online to get an appointment today.